Comprehensive Set: This package includes four wire piercing probes in two sizes (2mm and 4mm), ensuring compatibility with various devices. Each probe is crafted from high-quality PA and nickel-plated copper, offering enhanced durability and reliability for frequent use. Versatile Tool Sizes: Equipped with two jack sizes, 2mm and 4mm, these insulation piercing clips are designed to accommodate a wide range of electrical testing needs without damaging the wires. This flexibility allows for precise and safe measurements across different applications. Construction: Their robust design ensures they 't easily break or damage, providing you with a reliable tool for all your electrical testing tasks. Efficient Wire Testing: These probes enable direct contact with insulated wires, eliminating the need to cut or strip insulation. This feature not only saves time but also preserves the integrity of your wires, making it an essential tool for safe and effective electrical testing. Wide-Ranging